diff --git a/tests/typescript/declare/trailing-comma/__snapshots__/jsfmt.spec.js.snap b/tests/typescript/declare/trailing-comma/__snapshots__/jsfmt.spec.js.snap
new file mode 100644
index 000000000000..85ba83289673
--- /dev/null
+++ b/tests/typescript/declare/trailing-comma/__snapshots__/jsfmt.spec.js.snap
@@ -0,0 +1,43 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`function-rest-trailing-comma.ts - {"trailingComma":"all"} format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+trailingComma: "all"
+                                                                                | printWidth
+=====================================input======================================
+declare function foo(...args: any[], )
+=====================================output=====================================
+declare function foo(...args: any[]);
+
+================================================================================
+`;
+
+exports[`function-rest-trailing-comma.ts - {"trailingComma":"es5"} format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+trailingComma: "es5"
+                                                                                | printWidth
+=====================================input======================================
+declare function foo(...args: any[], )
+=====================================output=====================================
+declare function foo(...args: any[]);
+
+================================================================================
+`;
+
+exports[`function-rest-trailing-comma.ts - {"trailingComma":"none"} format 1`] = `
+====================================options=====================================
+parsers: ["typescript"]
+printWidth: 80
+trailingComma: "none"
+                                                                                | printWidth
+=====================================input======================================
+declare function foo(...args: any[], )
+=====================================output=====================================
+declare function foo(...args: any[]);
+
+================================================================================
+`;
diff --git a/tests/typescript/declare/trailing-comma/function-rest-trailing-comma.ts b/tests/typescript/declare/trailing-comma/function-rest-trailing-comma.ts
new file mode 100644
index 000000000000..4b2f60d50e23
--- /dev/null
+++ b/tests/typescript/declare/trailing-comma/function-rest-trailing-comma.ts
@@ -0,0 +1 @@
+declare function foo(...args: any[], )
\ No newline at end of file
diff --git a/tests/typescript/declare/trailing-comma/jsfmt.spec.js b/tests/typescript/declare/trailing-comma/jsfmt.spec.js
new file mode 100644
index 000000000000..dd71cc1bbda3
--- /dev/null
+++ b/tests/typescript/declare/trailing-comma/jsfmt.spec.js
@@ -0,0 +1,3 @@
+run_spec(__dirname, ["typescript"], {trailingComma: "es5"});
+run_spec(__dirname, ["typescript"], {trailingComma: "none"});
+run_spec(__dirname, ["typescript"], {trailingComma: "all"});